A vehicle air conditioning system conventionally includes a compressor, a condenser, an evaporator, and an accumulator arranged as a refrigerant circuit. The compressor compresses gaseous refrigerant for delivery to the condenser, where the state of the refrigerant changes from gaseous to liquid. The liquid refrigerant then passes to the evaporator, where an air blower circulates air over the evaporator to the vehicle passenger compartment. The consequent heat transfer from the ambient air to the evaporator causes the refrigerant to change to a mostly gaseous state.
The refrigerant then passes from the evaporator to the accumulator. The function of the accumulator is to separate any remaining liquid refrigerant from the gaseous refrigerant, allowing only gaseous refrigerant to return to the compressor. The residual liquid refrigerant eventually turns to a gaseous state and is then returned to the compressor. The accumulator also provides for recovery of lubricating oil contained in the refrigerant, returning a metered amount of the oil to the inlet side of the compressor.
The accumulator normally is an upright cylindrical housing with an inlet opening formed therein and having an outlet tube with its mouth near the top of the inside of the housing. Refrigerant from the evaporator is introduced into the accumulator through the inlet opening, which may be in the top or in the side of the accumulator housing. Suction created by the compressor draws gaseous refrigerant out of the accumulator through the outlet tube. A desiccant is usually provided to dry the refrigerant as it circulates through the accumulator.
To prevent any liquid refrigerant from entering the outlet tube and being drawn back into the compressor, some structure is typically provided to act as a shield for the mouth of the outlet tube. For example, U.S. Pat. No. 4,474,035 to Amin et al., assigned to the assignee of the present invention, discloses an accumulator having a domed baffle plate adjacent the accumulator opening. Liquid portions of the refrigerant are dispersed through the roof of the accumulator onto the domed baffle plate and the sides of the accumulator, allowing the gaseous components of the refrigerant to accumulate in the upper region of the accumulator adjacent the mouth of the outlet tube. The gaseous refrigerant then exits the accumulator through the outlet tube, which extends through the top of the accumulator.
Because vehicle space constraints such as low hoodlines often restrict the use of a top inlet or top outlet, accumulator designs with side inlets and/or side outlets have been proposed. For example, U.S. Pat. No. 4,291,548 to Livesay discloses an accumulator having a side inlet through which the incoming refrigerant is directed against a frustoconical shaped outlet tube shield. Similarly, U.S. Pat. No. 4,496,378 to Kish discloses an accumulator having a side inlet through which the incoming flow is directed against a deflector attached to the accumulator housing next to the inlet opening. Also, U.S. Pat. No. 4,528,826 to Avery, Jr. discloses an accumulator in which the incoming refrigerant is directed from a side inlet against the top of the accumulator housing. Gaseous refrigerant exits through an unshielded side outlet conduit, optionally after filtering through a desiccant.